Glossary

This is a glossary of technical terms related to SRB2 editing. Where applicable, click the link to the full Wiki article for more detailed information on the term.

3D block

* 3D block is another term for FOF.

Action

* An action determines an Object's behavior on the map during a certain state. It is responsible for controlling the Object's interaction with the level environment and other Objects.

Actor

* The actor of an action is the Object that performs it.

Blockmap

* The blockmap is a lump belonging to a map that is used for collision detection. It is usually created by a nodebuilder.

Constant

* A constant is a special keyword recognised by SRB2 which represents a specific integer number that cannot be changed by any means. Constants can be used in SOCs and Lua scripts in place of numbers when appropriate. FRACUNIT and TICRATE are common examples of constants, used with measurement of fracunits and tics respectively.

Control linedef

* A control linedef is a linedef that controls a special effect on the map. Examples of such special effects include FOFs and linedef executors. The control linedef is linked by its tag to the sector where the effect is performed, which is called the target sector. The sector that the control linedef is part of is called the control sector.

Control sector

* A control sector is a sector outside the main map that contains one or more control linedefs. Some of the control linedef's settings may be defined through the control sector's properties.

Cutscene

* A cutscene is a sequence of pictures and text that illustrates a part of a storyline in SRB2. Cutscenes can be played at the start of the game, between maps, and as the credits at the end of the game.

Desync

* Shorthand for desynchronization. SRB2's netcode relies on a lockstep model that requires every client to agree on where every player is in every frame. Due to a bug in the game or faulty scripting, whenever a particular client's data on the players' positions deviates from the server's, a desync occurs. By default, SRB2 resends the current game state data to the client who desynchronized so they're not kicked out of the game.

F_SKY1

* F_SKY1 is a special flat that displays the sky, instead of a typical floor or ceiling. The actual graphic used for the sky is set in the level header.

Flag

* A flag refers to one of a series of toggles that determine various properties of a component of the game. For example, Object flags specifically determine the properties of an Object. Similar groups of flags also exist for various other parts of the game such as linedefs and Things.

Flat

* A flat is a graphic that is displayed on either the ceiling or the floor of a sector.

FOF

* A floor over floor block, abbreviated as FOF, is a floating platform in a map. SRB2 provides different types of FOFs with different features, such as translucency or the ability to cast a shadow below them. FOFs are also used for certain special level elements, such as water and quicksand.

Fracunit

* A fracunit is a unit of distance measurement used in SRB2. Certain actions and Object properties use a more precise distance measurement, where one unit equals 1/65536th of a fracunit. In these contexts, SOCs and Lua scripts often supply the value in fracunits and then multiply them with the constant "FRACUNIT", in all-capital letters. This constant has a value of 65536, and thus converts the value from fracunits to the more precise distance unit. For example, an Object size of "2*FRACUNIT" means that the Object has a size of two fracunits, or 2*65536 = 131072 smaller units.

Freeslot

* A freeslot is a slot for an Object type, state, sprite or sound that is not occupied by SRB2 and can be filled with a custom entry without overwriting anything in SRB2 itself.

IWAD

* The IWAD, short for "internal WAD", is the WAD file that contains most of the game's resources. However, as of v2.2, SRB2 uses srb2.pk3 as its base resource.

Level header

* A level header is a SOC block that defines certain properties of a level such as its name, its sky graphic, and the background music.

Linedef

* A linedef is a line in a map that makes up part of the level geometry. An area enclosed by linedefs is called a sector. In the game, linedefs are visible to the player as the level's walls. Each linedef has one or two sidedefs that, among other things, determine the graphics displayed on the linedef, which are called textures.

Linedef executor

* A linedef executor is a special type of linedef that executes an interactively triggered event.

Lua

* Lua is the name of a scripting language used by SRB2, which can be used to create custom gamelogic.

Lump

* A lump is a chunk of data in a WAD or PK3 file.

Lump editor

* A lump editor is a program that manages the lumps of a WAD (and in some cases PK3) file. Lump editors are used to organize the contents of a WAD file and to edit some types of lumps, such as text lumps. Maps, however, are edited with separate programs called map editors. Examples of lump editors include SLADE and XWE.

MAINCFG

* MAINCFG is a lump in a WAD file that contains SOC data, such as game settings, unlockables, level headers or custom Objects.

Map

* A map is a level in SRB2. Its layout is described by sectors, linedefs, sidedefs, vertices, and Things.

Map editor

* A map editor is a program that allows the user to design maps, such as Zone Builder. Older examples include Doom Builder, SRB2 Doom Builder and SRB2 Workbench.

Node

*A node is a data structure in a map that is used for rendering purposes. Nodes are created by a nodebuilder.

Nodebuilder

*A nodebuilder is a program that generates data for a map that is used for rendering and collision purposes.

Object

* An Object is any kind of entity that exists on a map, such as the player, enemies, power-ups or scenery items. SOCs allow users to edit the properties of SRB2's Object types and create custom ones.

Palette

* The palette is the set of 256 colors that SRB2 can display at once. All graphics used in the game are restricted to these colors.

Patch

* A patch is an image that forms part of a composite texture.

PK3

* PK3 is a format for data files for SRB2, containing resources such as graphics, music and levels. Unlike WAD files, PK3 files are compressed and can include folders. A piece of data in a PK3 file is called a lump.

PolyObject

* A PolyObject is a group of linedefs that can move horizontally, which normal level geometry cannot. PolyObjects can be used to create moving and rotating platforms, for example.

PWAD

* A PWAD, short for "patch WAD", is a WAD file that contains data supplementary to the IWAD. This includes custom addons for SRB2 as well as some of the data files that come with SRB2, such as music.dta or player.dta.

REJECT

* REJECT is a lump belonging to a map that calculates which sectors are visible from each other. It is usually created by a nodebuilder.

Script

* A script is a text file that contains code that SRB2 can load and execute at runtime. There are three types of scripts for SRB2: Lua scripts are the most powerful and versatile of these, since they can be used to write custom game logic. SOCs allow the user to define custom data for various purposes. Finally, console scripts are used to automatically execute a series of console commands.

Sector

* A sector is an area in a map that is enclosed by linedefs. The graphics displayed on a sector's floor and ceiling are called flats.

Segment

*A segment, also called seg, is a section of a linedef that is created by a nodebuilder for rendering purposes.

Sidedef

* A sidedef is an individual side of a linedef. A linedef typically has two sidedefs, although in cases where only side will be visible in the map, it may have only one sidedef. The sidedefs determine the sectors the linedef belongs to, as well the graphics displayed on the walls, which are called textures.

Skin

A skin is a form of sprite replacement that can be applied to Objects, and allows players to play as a particular character. A skin is defined by a special lump called S_SKIN that determines the abilities, movement speeds and other statistics of a playable character; this is accompanied by a set of sprites that determine the appearance of the character itself. Three skins are included with SRB2 for the characters Sonic, Tails, and Knuckles.

Skin color

A skin color is a translation map that replaces a specified range of palette colors used in a sprite with other colors.

Slope

A slope is a surface that is not strictly horizontal but goes upwards or downwards at an angle.

SOC

* SOC, an acronym for Sonic Object Configuration, is the name of both a text-based content definition language for SRB2 and the scripts created in this language. SOC allows the user to customize a variety of SRB2's features, such as Objects, level headers and unlockables.

Sound

* A sound is a sound effect in SRB2. It is stored as lump in a WAD or PK3 file and can be played back interactively in a map either by Objects or through the use of linedef executors.

Sprite

* A sprite is a graphic displayed by an Object.

State

* A state is an animation frame of an Object that controls its behavior and appearance for certain period of time.

Sub-sector

*A sub-sector is a section of a sector that is created by a nodebuilder for rendering purposes.

Tag

* A tag is a number assigned to linedefs and sectors to link them together for certain special effects. For example, a control linedef and its target sector must be given the same tag.

Target

* The target is an attribute of an Object that refers to a second, related Object. Many actions require the actor to have a target that the action can be performed in relation to. For example, certain movement actions will make the actor move towards its target, while shooting actions will shoot a projectile towards the target.

Target sector

* A target sector is a sector in a map in which a special effect is performed. The type of special effect is controlled by a control linedef, which shares the same tag as the target sector.

Texture

* A texture is a graphic that is displayed on a sidedef, which appears as a wall in-game. A texture can be either a single image or a composite of several smaller images. In the latter case, the smaller images are called patches.

Thing

* A Thing is an item that can be placed inside a map. Most Objects, such as enemies, scenery items or rings, are placed on the map via Things. However, some Objects, such as projectiles, do not have a corresponding Thing type, and therefore cannot be placed directly on a map.

Thok barrier

* A thok barrier is an outer sector with height 0 that surrounds a part of a map or all of it. It is used in outdoor sections to create outer walls that show the sky. In previous versions of SRB2, it was necessary to prevent Sonic from thokking outside of the level boundaries and to allow Knuckles to climb on the outer walls of the level.

Tic

* A tic is a unit of time measurement used in SRB2, which is equal to 1/35th of a second. Because SRB2 runs at a framerate of 35 frames per seconds, a tic is the smallest unit of time that is discernible to the player. In SOCs and Lua scripts, time-related values are often given in seconds and then multiplied with the constant "TICRATE" , in all-capital letters. This constant has a value of 35, and thus converts the value from seconds to tics. For example, a state duration of "2*TICRATE" means that the state lasts two seconds, or 2*35 = 70 tics.

Tracer

* The tracer is an attribute of an Object that refers to a second, related Object. It is identical in function to the target, but it is used in different situations, such as when an action needs a second reference Object in addition to the target.

Trigger linedef

* A trigger linedef is a linedef that executes one or more linedef executors under certain conditions. The trigger linedef is activated when a trigger sector with the same tag is entered by the player or another Object. Depending on the type of the trigger linedef, certain conditions are then checked, and if the conditions are true, all linedef executors in the same sector will be executed.

Trigger sector

* A trigger sector is a sector that, when entered by the player or other Objects under certain conditions, triggers a linedef executor.

UDMF

* UDMF (Universal Doom Map Format) is a newer, more extensible map format, supported by SRB2 as of v2.2.11.

Vertex

* A vertex is a point on a map where a linedef begins or ends.

WAD

* WAD is a format for data files for SRB2, containing resources such as graphics, music and levels. A piece of data in a WAD file is called a lump.

WAD editor

* A WAD editor is a program that allows the user to edit WAD (and in some cases PK3) files. There are three types of WAD editors: lump editors, which are used to organize the data, map editors, which are used to design maps, and nodebuilders, which generate additional map data that is used by the game for rendering and collision purposes.